1. Field of the Invention
This invention relates to a method and device for changing motor oil, and, optionally, flushing the motor oil reservoir and crankcase components in internal combustion engines of all sizes. Such internal combustion engines can be found on automobiles, trucks, tractors, heavy earth moving equipment, military equipment, or the like. More particulaly, this invention relates to processes in which residual spent oil and other contaminants which adhere to the surfaces of the internal engine oil distribution channels of the engine components such as the crankshaft, bearings, connecting rods, etc, in the crankcase are expendiently removed. This invention also relates to a device and method for removing the degraded spent motor oil and replacing it with a suitable amount of fresh motor oil in an integrated self-contained process at high speeds with almost no exposure to the oil vapors of the spent engine oil.
2. Background of the Relevant Art
The benefits of routine oil changes to internal combustion engines are well known. Routine oil changes have been shown to increase engine life and performance. With repeated prolonged use, motor oil builds up metallic and non-metallic suspended particles from the abrasive and or adhesive wear of engine parts against one another and from products of incomplete combustion and improper air intake. The particles, in turn, cause abrasive wear of the engine bearings, piston rings and other moving parts and result in the reduction of the motor oil lubricity as various additives and lubricating components become depleted. This adversely effects engine performance and, if left unchanged, can destroy or cripple the engine performance. It is recommended by at least one oil manufacturer that the level of total solid concentration be limited to levels below 3.0% with levels of silica being present in amounts lower than 25 ppm and sodium in amounts lower than 200 ppm.
To obtain satisfactory automotive engine performance, and maintain solid concentration levels in the motor oil lower than the recommended 3.0%, changing the motor oil in an automobile engine is a necessary, but an undesirable, dirty, and time-consuming task. In currently designed vehicles, the oil pan serves the purpose of a reservoir for circulation of engine oil. Engine lubrication is generally accomplished through a gear-type pump. The pump picks up engine oil from the oil pan sump, where oil is drawn up through the pick-up screen and tube, and past through the pump to the oil filter. The oil filter is generally a full flow paper element unit. In some vehicles, an oil filter bypass is used to insure adequate oil supply, should the filter become plugged or develop excessive pressure drop. Oil is routed from the filter to the main oil gallery. The gallery supplies valve train components with oil, and by means of intersecting passages, supplies oil to the cam shaft bearings. Oil draining back from the rocker arms is directed, by cast dams in the crank case casting, to supply the cam shaft lobes. Oil also drains past specific hydraulic lifter flats to oil cam shaft lobes directly. The passages supplying oil to the cam shaft bearings also supply the crank shaft main bearings through intersecting passages. Oil from the crank shaft main bearings is supplied to the connecting rod bearings by means of intersecting passages drilled in the crank shaft. The front cam bearing can include a slot on its outside diameter to supply oil to the cam sprocket thrust face. In some engines, many internal engine parts have no direct oil feed and are supplied either by gravity or splash from other direct feed components. A bypass valve can also be disposed in the oil pick-up screen to insure adequate oil flow if the screen should become restricted. A pressure regulator valve, sometimes located in the oil pump body, maintains adequate pressure for the lubrication system and bypasses any excess back to the suction side of the pump. The full flow oil filter is generally mounted on a machined boss on the side of the engine. Oil from the pump passes through the filter before going to the engine oil galleries. In the filter, the oil passes through a filtering element where dirt and foreign particles are removed.
To remove contaminated oil, the drain plug, generally located in the lowermost region of the oil pan, is opened. The degraded (spent) oil containing suspended particles is permitted to flow under gravity out of the pan into a suitable receptacle. After the spent oil is removed, the used oil filter can be removed and replaced. The drain plug can, then, be replaced and fresh oil added to the engine; usually through a separate opening, such as in the engine valve cover.
The process of gravity drainage does not remove all of the spent oil with its metallic and non-metallic particulates because gravity drainage provides only minimum scrub cleaning or scouring action and cannot dislodge strongly adhering particulates and degraded oil components. A significant portion sticks to the oil pan walls, as well as to the surfaces and passages of engine components such as the crank shaft, connecting rods, pistons engine block, cylinder head and the like. These particles remain to be mixed with fresh motor oil. Thus the concentration of contaminants is lowered by dilution and only a part of the total contaminants are eliminated.
The oil change process is essentially the same whether performed at home, at service stations or at one of the various rapid oil change centers which have opened in recent years. Spent or dirty oil is allowed to collect in the oil pan and is, then, permitted to drain from the oil pan through the drain plug opening located in the lowermost portion of the oil pan. The drain plug opening is, then, closed and fresh oil is added to the crankcase and oil pan through a suitable opening such as the valve cover.
In this basic procedure, the oil pan and crankcase never drain completely. Oil containing suspended, gelatinous, and sticky particles remains on the walls of the pan and the surfaces of the crankcase components, and in the various oil distribution passages, to mix with the fresh oil added during the conventional oil change process and subsequent engine use. This reduces the life of the oil filter which, in turn, further reduces the life of the engine itself over an extended period of time.
Removal of the used oil filter is also a messy environmentally unacceptable and undesirable procedure. The used filter must be unscrewed and removed without spilling the large amount of oil remaining within it.
The commercially available oil change process is also limited by the time required for oil drainage. The flow rate, or time required for oil drainage, is the same for each of these locations, because it is limited by the size of the drain plug aperture and the force of gravity. Service stations and other locations simplify the process of oil drainage with the use of hydraulic racks, special oil collection receptacles and the like. However, this specialized and expensive equipment is not readily available to the typical automotive owner who may wish to change the oil in his vehicle at home. It has been estimated that the retail market of oil is approximately 2.83 billion quarts or approximately 700 million gallons. The do-it-yourself individual has been found to be price sensitive, and tends to distrust the quality of service stations and other oil change centers. The do-it-yourself individual typically believes that if you want a job done right, you do it yourself. However, the current design of vehicles does not lend itself to do-it-yourself oil changes in a convenient clean and effortless manner. Many vehicles have low ground clearance making it difficult to access the oil drain plug for removal of the spent oil, and also making it difficult to collect the oil without contaminating the surrounding environment.
Environmental protection is a prominent social issue in our present society. Therefore, it would be desirable to encourage do-it-yourself oil changers to perform this type of task in an environmentally safe manner. It is estimated that there are approximately 119 million privately owned passenger vehicles. These vehicles require approximately 360 million oil changes a year, using an average of 1.2 gallons per change based on an average oil change frequency of 2.94 times a year. This amounts to approximately 550 million gallons of motor oil a year. Of this amount, it is estimated that 70% of motor oil is installed by motorists themselves. It is believed that pursuant to present practice, the spent oil drained by motorists finds its way into spent household containers, such as milk cartons. The household containers are closed and disposed of in the garbage which can and will finally find its way into the local waste dump. As the house hold container deteriorates, the oil and its contaminates will eventually seep into the ground water surrounding below the dump site. It has been estimated that 6.6 million barrels of oil a year seeps into U.S. soil creating serious potential ground water pollution problems. It would be desirable environmentally and economically if this oil could be collected and recycled. In order to motivate the do-it-yourself market, it is desirable in the present invention to make the collection of oil from the oil pan as well as the fitting during oil changes effortless, clean and inexpensive.
Conservation of energy and the trade deficit are also major issues in today's society. It is estimated that 250-360 million gallons of spent oil can now be easily collected and profitably recycled. The price of spent oil so collected is four dollars per barrel at best, while the price of crude oil is much greater at approximately $18.00 per barrel. Recycling easily collected spent oil could decrease the trade deficit by approximately 120 million dollars, while providing a profitable recycling economy of approximately 86 million dollars per year.
Therefore, it would be desirable to provide a method which accelerates removal of spent oil from the oil pan and the filter more completely and easily from the crank case. It would also be desirable to provide a system which reduces the amount of spent oil handling as required in the conventional oil change service station. Finally, it is desirable to provide a method which could be easily employed by all the vehicle owners whether at home or at a convenient service station with all the benefits of the method of the present invention such as time savings, money savings, convenience, minimum exposure to motor oil, minimize pollution of land and waterways, energy conservation, trade deficit reduction, and finally longer lasting, better performing engines.